酸蚀时间、再矿化时间对乳牙釉质再矿化的影响

Effects of etching and re-mineralization time on enamel re-mineralization of deciduous teeth

目的本研究采用激光共聚焦显微镜来观测不同酸蚀时间、不同矿化时间对乳牙釉质再矿化的影响。方法采用随机区组设计,将28枚离体乳切牙的唇面分别开4个窗,随机分到酸蚀30 s、60 s、90 s、120 s 4个处理组中,采用32%磷酸凝胶对标本进行酸蚀处理,而后采用人工唾液进行再矿化,分别于脱矿后、再矿化处理2 h,再矿化处理24 h进行激光共聚焦显微镜扫描,记录其平均荧光量(AF),采用重复测量的方差分析对数据进行分析,显著性水平为0.05。结果多变量方差分析(MANOVA)结果显示:再矿化时间、酸蚀时间对再矿化后AF有显著影响(分别F=357.74,P<0.0001;F=51.62,P<0.0001);Bonferroni法多重比较显示:酸蚀时间对再矿化效果影响中,除90 s组与120 s组之间的差异没有显著性,其余各组AF两两比较差异均有显著性;矿化时间对再矿化的影响中,两两比较AF差异均有显著性。结论在进行乳牙抗酸能力及再矿化潜能检测时,酸蚀时间不可超过60 s,再矿化时间可以为24 h。

Objective To study the effects of etching time and remineralization time on the enamel re-mineralization of deciduous teeth using cofocal laser scanning microscopy（CLSM）.Methods Twenty-eight primary incisors were used in this experiment.Four rectangular windows were created in the labial surface of each incisor,randomly assigned to four treatment groups（Group A,B,C,D）.The windows in group A,B,C,D were etched 30 s,60 s,90 s and 120 s,respectively,with 32% phosphoric acid gel.All the samples were rinsed and re-mineralized in artificial saliva for 0 h,2 h,24 h.CLSM was applied to study the de-/re-mineralization.Average Lesion Fluorescence（AF） for each sample was recorded at each time point of 0 h,2 h,24 h.The data were analyzed with repeated measurement.The significance was 0.05.Results The results of MANOVA showed both etching time and re-mineralization time had a significant effect on the value of AF（F=357.74,P0.0001;F=51.62,P0.0001,respectively）.Bonferroni analysis indicated that the difference of AF between each group was significant except that between 90 s and 120 s.The difference of AF between each time point within each group was significant.Conclusions It was inferred the etching time was no more 60 s,and the re-mineralization time may be 24 h when the acid-resistance and remineralization potential of primary teeth were examined.